1. Field of the Invention
The present invention relates both to a curable composition comprising an olefin polymer having hydrolysable silane groups and a latent compound, and to a method of fabricating a cured article from said curable composition.
The invention applies typically, but not exclusively, to fabricating cured articles of the type comprising an insulating layer on an electrical and/or optical cable, or of the type comprising a tube or a pipe for transporting water, oil, or gas.
2. Description of the Related Art
Present techniques for curing polymer compositions that are based on a polyolefin that includes hydrolysable silane groups make use of curing catalysts of the tin salt type, such as, for example dibutyl tin dilaurate (DBTDL). Nevertheless, those catalysts are harmful for the environment and, according to forthcoming regulations, they are going to need to be replaced by catalysts that are less polluting.
To mitigate that drawback, document EP-1 256 593 proposes curing a polyethylene-based composition by using a curing catalyst comprising an aromatic sulfonic acid ArSO3H or a precursor thereof, where precursors are compounds that are suitable for being converted into aryl sulfonic acid by hydrolysis. Nevertheless, aromatic sulfonic acid and the precursors thereof are compounds that are very sensitive to moisture. As a result their storage and utilization time is very limited. Furthermore, that catalyst does not guarantee that no gel forms during the extrusion step, as a result of premature catalysis of curing in an extruder.